Over time, television has evolved from black and white images to color images and now high definition. Currently, some manufacturers of television equipment have begun to market products capable of originating and displaying images in three dimensions (3D). The newly emerging 3D television displays currently incur several sources of visual discomfort, including: keystone distortion, depth plane curvature, magnification, miniaturization effects, shear distortion, cross-talk, picket fence effects and image flipping. In addition, visual discomfort can also arises from the lack of depth cue, e.g., picture areas with high motion, resulting in blurriness. Viewers often experience an uncomfortable feeling when viewing areas in an image having a lack of depth cue. Differences in random noise associated with film grain in the left-eye and right eye views of a 3D image can also cause strange visual effects to appear.
The addition of a dither signal to a digital image can reduce human sensitivity to coding artifacts, such as contouring and blocking artifacts, and can improve subjective quality. Adding noise, typically referred to as “Comfort noise” to video serves to achieve this goal. While technique for adding comfort noise to a two dimensional image exist, no known techniques exist for comfort noise to a 3D image.